import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.DatagramChannel;
public class MainClass {
public static void main(String[] args) throws Exception {
DatagramChannel channel = DatagramChannel.open();
DatagramSocket socket = channel.socket();
SocketAddress address = new InetSocketAddress(9999);
socket.bind(address);
ByteBuffer buffer = ByteBuffer.allocateDirect(65507);
while (true) {
SocketAddress client = channel.receive(buffer);
buffer.flip();
channel.send(buffer, client);
buffer.clear();
}
}
}